Apparatus and method for frothing milk

ABSTRACT

A jug for use with a frothing apparatus. The jug comprising: a vessel body for holding a liquid to be heated; a handle attached to the vessel body, the handle for holding the jug; a user interface for receiving an operation-related user input; a communication means adapted to communicate data associated with the jug to the frothing apparatus; and a controller for controlling the user interface and the communication means. In an embodiment, The frothing apparatus comprises: a steam heater, a steam nozzle, and a steam path providing fluid communication from the steam heater to the steam nozzle for delivering heating steam to the jug; communication means adapted to receive operating data from a cooperating communication means associated with the jug, the data comprising an operation-related user input; and a controller for controlling operation of the steam heater and the steam path based on the operation-related user input.

FIELD OF THE INVENTION

The invention relates to milk frothing and more particularly to methodsand apparatus for milk frothing in an espresso making machine having asteam wand.

BACKGROUND OF THE INVENTION

Any discussion of the prior art throughout the specification should inno way be considered as an admission that such prior art is widely knownor forms part of the common general knowledge in the field.

Steamed milk is used in the preparation of drinks such as latte,cappuccino and other hot beverages. When steamed milk is prepared in ajug, steam or a mixture of steam and air is generally introduced intothe milk through a wand. However, the construction of a wandincorporating a temperature sensor such as a thermistor and also adaptedto convey steam or a steam and air mixture is somewhat complicated and asystem incorporating such a wand would benefit from simplification.

A steam wand has an end that is submersible into a container of milk.The wand injects steam or a mixture of steam and air into the milk. Theend product is a milk froth. A milk froth has a target temperature andfroth texture. Different milk froth textures are required for differentbeverages. Texture refers to the air content and bubble sizedistribution in a froth. Achieving the correct temperature and texturein the finished froth product requires either a skilled operator or afrothing device that is at least partially automated. The content of theApplicant's PCT patent application. WIPO publication numbers WO2012/151629 is incorporated herein by reference.

SUMMARY OF THE INVENTION

According to an aspect of the invention there is provided an apparatusfor milk frothing.

According to an aspect of the invention there is provided a coffeemaking and/or milk frothing apparatus that includes: a steam source andan air source coupled to an air injector module for mixing the air andsteam.

Preferably, a solenoid controls release of steam flow to a steam wandvia an air injector module.

Preferably, the air injector module includes a primary steam flow path,an air injection path and an outflow. More preferably, the air injectionmodule can incorporate a venturi. Most preferably, the air injectionflow path can receive pressured air delivered by an air pump. Further,the mixing device may be a simple T-piece device, or a T-piece venturi,that combines two fluid flow paths.

Preferably, a pressure sensor is coupled to the air ingress flow path.The pressure sensor may provide pressure measurements to the processormodule.

According to an aspect of the invention there is provided a removabledrip tray having a temperature sensor.

According to an aspect of the invention there is provided a jug forsteaming milk. The jug may enable milk to be steamed via a detachablespigot through which steam or steam and air are introduced into the jug.

According to an aspect of the invention there is provided a milksteaming jug having a port for receiving a spigot, the spigot adapted tocarry steam or a steam and air mixture and inject same into an interiorof the jug.

According to an aspect of the invention there is provided a coffeemaking machine to have a spigot that carries a steam or steam and airmixture, the spigot being insertable into a cooperating jug having aport for receiving the spigot.

According to an aspect of the invention there is provided a coffeemaking machine having a spigot for conveying a steam or a steam and airmixture to a cooperating jug.

According to an aspect of the invention there is provided a steamed milkmaking machine to have a spigot that carries a steam or steam and airmixture, the spigot being insertable into a cooperating jug having aport for receiving the spigot.

According to an aspect of the invention there is provided a steamed milkmaking machine having a spigot for conveying a steam or a steam and airmixture to a cooperating jug, the machine also having a temperaturesensor that makes contact with an exterior of the jug when the jug isaffixed to the spigot.

According to an aspect of the invention there is provided a method andapparatus for creating steam and air mixtures within the steam boiler ofan espresso machine.

According to an aspect of the invention there is provided a remoteaccessory such as a milk frothing jug that can provide user inputs toand feedback from a milk frothing process.

Preferably, the remote appliance can communicate with a respectiveappliance, the remote appliance may communicate with the respectiveappliance by way of wireless and/or wired communication. The remoteappliance may include a temperature sensor for monitoring temperatureassociated with the remote appliance. Data indicative of the temperaturemay be transmitted to the appliance.

According to an aspect of the invention there is provided an apparatusfor making espresso coffee, the apparatus including:

-   -   a body having a steam vessel and a pressurised air source and a        steam wand; the steam vessel having a heating element for        providing a steam source; the pressurised air source coupled to        steam vessel for delivering an air supply to the steam vessel;        the steam wand being coupled to the steam vessel via an        air-steam flow path there between for receiving an air-steam        source; an output control valve, located in the steam flow path,        controls the steam source there through; an electronic        controller module within the body; the electronic controller        module adapted to control operation of the heating element,        pressurised air source and output control valve;    -   a removable jug device including a processor element wirelessly        couplable to the controller module; the jug device including a        temperature sensor element for measuring temperature of fluid        within the jug; temperature sensor element being coupled to        processor element for enabling the processor element to transmit        a signal indicative of a measured temperature to the control        module; the steam wand delivers an air-steam mixture to the        fluid;    -   a user interface module coupled to the controller module for        providing user input to the controller module; the control        module receives user input of a selected temperature and        selected texture; the control module, using the selected        texture, determines a mixture of air and steam to specify an        air-steam flow; the control module controls the pressurised air        source and output control valve to deliver the specified        air-steam flow during a frothing cycle; the control module        receives the signal indicative of the measured temperature and        closes the discharge valve when the measured temperature reaches        the selected temperature to end the frothing cycle.

According to an aspect of the invention there is provided an apparatusfor making espresso coffee, the apparatus including:

-   -   a body having a steam vessel and a pressurised air source and a        steam wand; the steam vessel having a heating element for        providing a steam source; the pressurised air source coupled to        steam vessel for delivering an air supply to the steam vessel;        the steam wand being coupled to the steam vessel via an        air-steam flow path there between for receiving an air-steam        source; an output control valve, located in the steam flow path,        controls the steam source there through;    -   an electronic controller module within the body; the electronic        controller module adapted to control operation of the heating        element, pressurised air source and output control valve;    -   a removable jug device including a processor element wirelessly        couplable to the controller module; the jug device including a        temperature sensor element for measuring temperature of fluid        within the jug; temperature sensor element being coupled to        processor element for enabling the processor element to transmit        a signal indicative of a measured temperature to the control        module; the steam wand delivers an air-steam mixture to the        fluid;    -   a user interface module coupled to the controller module for        providing user input to the controller module; the control        module receives user input of a selected temperature and        selected texture; the user interface including a variable user        input for specifying the selected texture; the variable user        input directly regulates the operation of an air pump that        provides the pressurised air source; the variable user input        provides a feedback signal to the controller for indicating the        selected texture; the control module activates the pressurised        air source and output control valve to deliver the specified        air-steam flow during a frothing cycle; the control module        receives the signal indicative of the measured temperature and        closes the discharge valve when the measured temperature reaches        the selected temperature to end the frothing cycle.

The apparatus may have a removable jug device that includes secondaryuser interface forming a portion of the user interface for enabling userinput of the selected temperature and/or the selected texture.

The apparatus may have steam wand that is associated with a positionsensor that can indicate when the steam wand is returned to an uprighthome position; such that a cleaning cycle is initiated only when thesteam wand is in the upright home position.

The apparatus may have an output control valve that selectively operatesas either fully closed, open to an overflow path or open to air-steamflow path. The overflow path may be in communication with a drip tray.

The apparatus may have a output control valve that is in the form of a3/2 solenoid output control valve; the valve having a valve sensor thattransmits a signal indicative of a valve position to the controllermodule; the controller module causing the valve position to be indicatedon the user interface.

The apparatus may have a variable user input that is used to specify theselected texture. The apparatus may enable user selection of temperatureand/or texture that can be adjusted during the frothing cycle. Thepressurised air source may be continuously adjusted by the controllermodule during a frothing cycle to provide differing quantities of airfrom full flow rate to no flow.

The apparatus may have pressurised air source that is supplied by apositive displacement pump that delivers pressurised air to the boiler,

The apparatus may have a gas mixer located in the air-steam flow pathfor enhancing combining of the discharged air and steam.

The apparatus may further includes one or more of the following sensorscoupled to the controller module a boiler temperature sensor formonitoring temperature within boiler; a boiler humidity sensor formonitoring humidity within the boiler; a pressure sensor for monitoringpressure within the boiler; a level sensor for monitoring fluid levelwithin the boiler; and a pressure sensor for monitoring temperature offlow in the air-steam flow path; one or more of the following sensorsproviding a signal for selective display on the user interface.

The apparatus may have a processor element of the removable jug devicethat is connected to the controller module via a wireless interface. Thewireless interface may be bi-directional. The wireless interface may usea near field communication protocol. Electrical power can be wirelesslycommunicated to the removable jug device.

The removable jug device can includes a second user interface thatincludes user inputs to selectively define operation parameters relatingto the finished frothed product and sensing devices such as atemperature sensor.

User adjustable input parameters may include froth amount and/or frothvolume and/or froth temperature and/or selecting flow start and/orselecting flow start stop.

According to an aspect of the invention there is provided a jug for usewith a frothing apparatus, the jug comprising:

-   -   a vessel body for holding a liquid to be heated;    -   a handle attached to the vessel body, the handle for holding the        jug;    -   a user interface for receiving an operation-related user input;    -   a communication means adapted to communicate data associated        with the jug to the frothing apparatus; and    -   a controller for controlling the user interface and the        communication means.

The jug may further comprise a temperature sensor adapted to measure atemperature of the liquid or of a wall of the vessel body.

The jug may further comprise a power means adapted to provide power foroperation of the user interface, the communication means and thetemperature sensor. The power means may comprise a power storage, andwherein the power storage is chargeable via wireless transmitted powersignals received via the communication means.

The communication means may comprise a wireless communication means. Thewireless communication means may comprise a radio frequency (RF)transceiver and wherein the frothing apparatus is adapted to receive thecommunicated data via a cooperating radio frequency (RF) transceiver.The communication means may be bidirectional, and the communicationmeans maybe adapted to receive data from a group consisting of: frothingapparatus status data, heating process status data, and wirelesstransmitted power signals.

Data associated with the jug may be selected from a group consisting of:the operation-related user input and the measured temperature. Theoperation-related user input may be selected from a group consisting of:a temperature setting, a froth setting, a start selection and a stopselection. The operation-related user input may comprise an additionaluser input received after heating of the liquid has commenced.

The handle may carry the user interface, the communication means, thetemperature sensor, the power means and associated electrical and/orelectronic components; and wherein the handle is removably attached tothe vessel body of the jug.

The user interface may comprise a display, and wherein the display isadapted to display information associated with the operation-relateduser input and/or data received via the communication means from thefrothing apparatus.

According to an aspect of the invention there is provided a frothingapparatus adapted to cooperate with t jug for heating a liquid in thejug, the frothing apparatus comprising:

-   -   a steam heater, a steam nozzle, and a steam path providing fluid        communication from the steam heater to the steam nozzle for        delivering heating steam to the jug;    -   communication means adapted to receive operating data from a        cooperating communication means associated with the jug, the        data comprising an operation-related user input; and    -   a controller for controlling operation of the steam heater and        the steam path based on the operation-related user input.

The operating data may further comprise measured temperature data,wherein the controller is adapted to control the operation of the steamheater and the steam path based on the measured temperature data.

The frothing apparatus may further comprise a pressurised air sourcecoupled to the steam heater for delivering an air supply to one or moreof the steam heater, the steam path or the steam nozzle for adding frothto the liquid being heated.

The operation-related user input may be selected from a group consistingof; a temperature setting, a froth setting, a start selection and a stopselection.

The communication means may comprise a wireless communication means. Thewireless communication means may comprise a radio frequency (RF)transceiver. The communication means may be bidirectional, wherein thecommunication means is adapted to send data to the jug, the sent dataselected from a group consisting of: frothing apparatus status data,heating process status data, and wireless transmitted power signals.

According to an aspect of the invention there is provided an espressomaking machine comprising a frothing apparatus as disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the invention will now be described, by way ofexample only, with reference to the accompanying drawings in which;

FIG. 1 is a schematic diagram of an espresso making machineincorporating a steamer spigot;

FIG. 2 is a perspective view of the jug used with the espresso makingmachine in FIG. 1;

FIG. 3 is an exploded perspective view of a milk steaming jug andcooperating milk steaming spigot;

FIG. 4 is a cross-sectional view of a steamer spigot inserted into asteamer jug having a check valve;

FIG. 5 is a cross-sectional view of a steamer spigot and steamer jugshowing the spigot disconnected from the steam source, but connected tothe jug;

FIG. 6 is a cross-sectional view of a steamer spigot and steamer jug,with the spigot disconnected from the jug and the steam source;

FIG. 7 is a perspective view of a section of a coffee machineillustrating steamer spigot, its cover, the jug alignment feature andprotruding temperature sensor;

FIG. 8 is a schematic cross-section of a jug with alignment groove incontact with an alignment feature and temperature sensor;

FIG. 9 is a perspective view illustrating the interaction between asteamer jug and retractable spigot cover;

FIG. 10 shows cross sections in elevation and plan view of a jug andspigot arrangement incorporating a ball valve, shown in the closedposition;

FIG. 11 shows cross sections in elevation and plan view of a jug andspigot arrangement incorporating, a ball valve, shown in the openposition;

FIG. 12 is schematic diagram of an espresso making machine in which asteam and air mixture is produced in, and dispensed from, a steamboiler;

FIG. 13 is a schematic diagram of an espresso making machine thatdispenses a user varied mixture of steam and air to a frothing wand;

FIG. 14 is a schematic diagram of an espresso making machine in which asteam and air mixture is produced in, and dispensed from, a steamboiler;

FIG. 15 is a schematic diagram of an, embodiment espresso makingmachine;

FIG. 16 is a schematic diagram of another embodiment espresso makingmachine;

FIG. 17 is a flow chart for a method of frothing milk;

FIG. 18 is a graph depicting a transducer control cycle;

FIG. 19A and FIG. 19B show an embodiment milk frother apparatus;

FIG. 20A through FIG. 20F show configurations of an embodiment milkfrother apparatus;

FIG. 21A and FIG. 21B show an embodiment milk frother apparatus;

FIG. 22A through FIG. 22F show configurations of an embodiment milkfrother apparatus;

FIG. 23 shows an example embodiment drip tray having an inbuilttemperature sensor;

FIG. 24 shows the drip tray of 23, having the temperature sensingapparatus in a raised configuration;

FIG. 25 shows the drip tray of FIG. 23, having the temperature sensingapparatus in a lowered configuration (biased upwards);

FIG. 26A and FIG. 26B show an embodiment coffee making and/or milkfrothing apparatus, having a removable drip tray;

FIG. 27A and FIG. 27B show an embodiment coffee making and/or milkfrothing apparatus, having a removable drip tray;

FIG. 28 shows an embodiment removable drip tray having a couplingelement comprising an electrical coupling and waste water/steamcoupling;

FIG. 29 shows an enlarged view of the coupling element of the drip trayof FIG. 28;

FIG. 30A shows an embodiment jug for frothing milk, shown with detachedhandle;

FIG. 30B shows an enlarged partial cross section view of the embodimentjug of FIG. 30A;

FIG. 31A shows an embodiment jug for frothing milk, shown with anattached handle;

FIG. 31B shows an enlarged partial cross section view of the embodimentjug of FIG. 31A;

FIG. 32A shows an embodiment handle for a jug of FIG. 30A; and

FIG. 32B shows the embodiment handle of FIG. 32A;

PREFERRED EMBODIMENT OF THE INVENTION

Steamer Jug

As shown in the example of FIG. 1, an espresso making machine 100comprises a water tank 101 that is associated with a pump 102 thatsupplies water to a heat exchanger 103 in a steam boiler 104. Water thuspre-heated by the heat exchanger 103 is supplied to a second boiler 105that provides hot water to a group head 107 or group element 106. Hotwater discharged from the group head 107 is used to brew espresso coffee108. It will be appreciated that other arrangements may be utilised tobrew coffee.

The water tank 101 is also associated with a second pump 109 thatsupplies water to the steam boiler 104. The steam boiler 104 dischargesto a solenoid controlled valve 110. Steam discharged from the valve 110flows through a venturi 111. The supply of steam passing through theventuri 111 may be augmented with a flow of air either drawn through theventuri's suction port 113 or otherwise augmented with an air pump 112that discharges into the venturi's suction port 113. A one-way valve 114prevents back flow into the optional air pump 112. Accordingly, steam ora mixture of steam and air that is used to steam milk located in a jug116 is discharged from the venturi 111 via a steam discharge 115.

It will be appreciated that the above referenced example is controlledfrom a main printed circuit board or other form of controller 117 thatreceives the various inputs and signals from the espresso making machine100 and provides the necessary output signals to power and control thedevice. The controller 117 also operates one or more graphic userdisplays and indicators that are present generally on the front surfaceof the espresso making machine 100. Such displays may include a graphicdisplay associated with the device's coffee grinder and tamping augerassembly 118, a display 119 associated with the steam or steam and airmixture produced by the espresso making machine 100 and another displayor display area 120 associated with the other functions performed by theespresso making machine 100.

The espresso making machine 100 has an externally mounted steam lever121 that can be activated by a user. When the lever 121 is activated,the processor or controller 117 causes either steam or a steam and airmixture to flow through the steam discharge 115 to a steamer spigot 122.The spigot 122 is adapted to be removably coupled to a removable milksteaming jug 116.

As shown in FIG. 2, a steamer jug 116 as illustrated in FIG. 1 comprisesa metallic (or at least partially metallic) open-ended body 200 having ahandle 201. A lower portion of the body 200 is covered by a base 203through which protrudes a port or inlet 202. The base may be polymericor metal or other suitable material. The port 202 is sized and shaped toreceive a steamer spigot. The part also retains a check valve or one-wayflow valve 204. In some embodiments the body 200 and base 203 areintegrally formed of the same material.

Aspects of the construction of the steamer spigot 300 are illustrated inFIG. 3. As suggested by FIG. 3 through FIG. 6, a spigot body 301 ispartially contained within an overflow valve body 302. In preferredembodiments, the overflow valve body 302 is affixed to an overflow valve303.

The overflow valve body 302 or valve 303 are preferably affixed to thecoffee making or steam making machine. The overflow valve 303 has atapered nozzle 304 that mates with a tapered nozzle seat 305 formedwithin a distal end of the spigot body 301. A groove 306 is locatedadjacent to the tapered nozzle 304 and receives an O-ring 307 thatenhances the seal between the tapered nozzle 304 and tapered nozzle seat305. A proximal and cylindrical end 308 of the spigot body 303 isremovably received within the valve body 309 which is itself removablyretained by the jug body 200. The valve body 309 carries within it avalve seat 310. The valve seat 310 has (for example) a cylindrical,internal bearing surface 311 that receives the shaft 312 of areciprocating valve sealing member 313. Other check valve types may beused. The valve body 309 is received within a spigot receiving socket316 that is integral with the metallic jug body 200. The open-end 317 ofthe spigot receiving socket is accessible through the port 202 thatpasses through the jug base 203. An opposite or submerged end of thesocket 316 is capped with a steam nozzle 314 having one or more throughopenings 315.

As shown in FIG. 4 the jug's steamer socket 400 semi-permanently retainsthe valve body 401.

It is held in place by friction or mechanical means and stays in placewhen the spigot body 301 is withdrawn from it.

The reciprocating valve 402 within the valve body 401 is supported bythe valve seat 403. Because it is supported by the cylindrical bearingsurface 404 of the valve seat 403, the valve reciprocates between openand closed or sealed orientations. A compression spring 405 biases orurges the valve to close 402 because it is inserted between the enlargeddistal head 406 of the valve stem and a distal surface of the valve sent403. The pressure exerted by the steam or steam and air mixture exitingthe spigot 407 is enough to overcome the bias exerted by the spring 405and to drive the valve's head 408 out of engagement with the cooperatingvalve seat 409. In preferred embodiments, the valve seat 409 is of aspherical kind and the seat contacting surface of the valve's head 408is also of a spherical kind. The head 408 is sized to the interior ofthe valve body 401 to maximise the forces acting on the valve 402.

In FIG. 4, the open proximal end of the spigot 407 has a circumferentialgroove containing an O-ring 450. The O-ring 450 creates a seal betweenthe spigot 407 and the valve body 401 and contributes friction thatprevents the spigot 407 from being prematurely ejected from the valvebody 401.

When fully inserted, as suggested by FIG. 4, the tapered nozzle 410 isin sealing engagement with the tapered nozzle socket 411 and the sealbetween them is further provided by or enhanced with the nozzle'scircumferential O-ring 412. Accordingly, steam or a steam and airmixture entering from the distal end of the overflow valve 413 willexert a force on the head 408 of the valve 402 and open it. The steam orsteam and air mixture will thus enter the interior of the valve body andbe discharged into the interior 414 of the jug via the through openings415 in the steam nozzle 416. An optional circumferential groove 417around the exterior of the valve body reduces excessive friction betweenthe valve body and the steamer socket, allowing it to be removed forcleaning, maintenance or repair, but not when the nozzle is withdrawn.

In the embodiment of FIG. 4, a compression spring 420 is located betweenthe overflow valve body 421 and the spigot. In this example, a latchassembly 430 prevents the overflow valve body from being inadvertentlyseparated from the distal end of the spigot.

The latch assembly 430 comprises a mechanical latch 431 having a pivot432 located between the distal end 433 and the working end or head 434of the latch 431. A tension spring 437 urges the head 434 intoengagement with a radially extending flange 435 formed on the spigot.The solenoid 436 may be activated to disengage the head 434 from theflange 435. The tension spring 437 returns the head 434 to the locked orengaged orientation.

An optional temperature sensor 438 (such as a NTC thermistor) may beattached to or affixed to the espresso or steam making machine 439 sothat the sensor tip 440 makes contact with an exterior surface 441 ofthe jug when the jug is seated. The temperature sensor 438 may be biasedtoward the jug or urged in the direction of the jug by, for example, acompression spring 442. Temperature data is be conveyed to thecontroller 117 from the temperature sensor 438. In some embodiments thedata connection is a wired connection from the sensor 438 to thecontroller 117. In other embodiments the data connection is a wirelessconnection such as a wireless RF signal.

In some embodiments the temperature sensor 438 is attached to or affixedto the jug 116 itself, and where the jug is removable, the dataconnection is a wireless connection and the data transmitter is locatedin, 011 or adjacent the jug.

As shown in FIG. 5, once the delivery of steam or steam and air hasceased, the spigot 501 may be withdrawn from the overflow valve body500. A through opening 502 in the side wall of the overflow valve bodyallows any discharge from either the nozzle or the overflow valve 503 tobe discharged. When the latch 504 is disengaged from the spigot's flange505 the compression spring 506 reverts to its original shape as the jugand nozzle are displaced away from the fixed overflow valve body 500.FIG. 5 also illustrates that an exterior surface of the jug mayincorporate a small indentation 507 for receiving and increasing thesurface area of contact between the jug 508 and the tip of thetemperature sensor 509.

As illustrated in FIG. 6, the jug 600 can be disengaged from the spigot,simply by overcoming the friction imposed by the spigot and/or its sealor O-ring 450.

As shown in FIG. 7, a coffee machine 700 has a base 701 adapted toreceive a milk steaming jug 802 (see FIG. 8 and FIG. 9). The base 701 isadjacent to a sidewall 702 of the machine through which the steamerspigot 703 protrudes. A retractable cover 704 is provided to divertinadvertent discharge of steam from the spigot 703 when the spigot isnot connected to a cooperating jug. The cover 704 is biased upward by aspring 710 and pivots about its lower end 705. The cover 704 covers thespigot's discharge opening when it is in its upright orientation (asillustrated). An upper surface of the machine's base 701 is alsoprovided with a raised or protruding alignment feature 706. In thisexample, the alignment feature 706 is a raised hump that is sized andshaped to cooperate with an alignment groove 806 on the underside of ajug 802, as shown in FIG. 8. In the embodiment shown, the raisedalignment feature 706 features an opening 707 through which protrudes atip of a temperature sensor 708 (such as a NTC thermistor).

As described elsewhere herein, the temperature sensor may also form partof the jug or be attached to the jug, and as such be separate from theespresso machine or from the milk frother.

As shown in FIG. 8, the stainless steel reservoir 801 of the jug 802 hasa necked or reduced diameter lower portion 803 that receives a polymericjug base cover 804. Although the lower surface 805 of the preferablymetal reservoir is flat, the underside of the cover 804 features a fullwidth groove 806 that conforms in shape to the alignment feature 706.Because the lip of the temperature sensor 708 is preferably rounded, itslips into a through opening 807 in the alignment groove 806 so as tomake contact wit h an underside of the stainless steel bottom 805 of thejug's reservoir 801.

In other embodiments the jug does not include a cover, and the basetogether with the features of the jug base (including the aligninggroove) are integrally formed with the jug, for example from metal.

As shown in FIG. 9, a jug 802 is introduced onto the steam nozzle 901 bylocating the underside of the base cover 804 onto the flat upper surface of the coffee machine's base 701 so the jug rests on the base 701.The jug 802 can then be slid along the alignment feature 706. Thespacing between the alignment feature 706 and the spigot 703 ensuresthat the spigot 703 will enter the spigot receiving socket, as suggestedby FIG. 4 through FIG. 6. As the jug 802 approaches the spigot 703, thejug will depress the spigot cover 704 so that it does not interfere withthe engagement between the spigot and the jug. When the jug iswithdrawn, the spigot cover 704 will return to its upright position asshown in FIG. 7 owing to the bias element 710.

As shown in FIG. 10 and FIG. 11, a jug 1000 for steaming milkincorporates a valve body 1001 in which is located a hall valve 1002.The ball valve 1002 is located between a valve seat 1003 and theperforated steam nozzle 1004. The ball valve 1002 is associated with anactuating shaft 1005 that is rotated from the open position to theclosed position by the action of a push pin 2006. The push pin isactuated by a processor controlled solenoid 1007 having an output pin1008 that is adapted to enter an opening 1009 adjacent to the valve bodyor spigot port 1010. The solenoid 1007 may be carried by the steamspigot 1015.

The processor will not actuate the solenoid 1007 unless the latch 1051is engaged with the spigot. When the output pin 1008 is extended, itimpinges on a proximal end of the push pin 1006. The distal end of thepush pin 1006 acts on a lever or cam or the like associated with therotating actuating shaft 1005. The lever or cam 1011 is biased into aclosed position by a bias element 1012, spring, leaf spring or the like.As shown in FIG. 11, actuation of the solenoid 1007 causes anadvancement of the actuating shaft 1008 which in turn advances the pushpin 1006. The push pin rotates the actuating shaft 1005 against the biasof the spring element 1012 to place the preferably ceramic ball elementof the ball valve 1002 into an open position wherein steam can exit thespigot, then pass through the ball valve 1002 and nozzle 1004. Thereturn of the push pin 1006 to the closed position can be assisted by asecond bias element or compression spring 1013.

Milk Frothing Apparatus

As shown in FIG. 12, an espresso making machine 1100 has within it asteam boiler not. In this example, the steam boiler 1101 has an internalheating element 1102 and an internal heat exchanger 1103 that may beused for heating or pre-heating hot water for brewing purposes.

Water is introduced into the steam boiler 1101 and is heated by theheating element 1102 to produce steam. The temperature of the contentsof the steam boiler 1101 is monitored by a temperature sensor 1104 suchas an NTC thermistor that communicates with the device's electroniccontroller 1105. In this example, the steam boiler 1101 is alsoassociated with a humidity sensor 1106 that measures and communicatesthe humidity of the contents of the boiler 1101 by sending a signal tothe controller 1105. The internal humidity of the steam boiler can bevaried by introducing pressurised atmospheric air into the steam boiler1101.

In this example, an air pump 1107 under the control of the controller1105 delivers an air supply to a pressure controller 1108 that is alsocontrolled by the controller 1105. The output of the pressure controller1108 is moderated by a flow control module 1109 in this example.Adjustment to the flow control module by the controller 1105 will alterthe air flow rate provided to the input of the solenoid valve 1119. Inthe alternative the air pump 1107 can deliver its air supply to apressure sensor 1108a that communicates with the controller 1105. Thisallows the controller 1105 to regulate the pump 1107 in accordance withthe output of the sensor 1108 a. A pressure sensor 1120 may also beassociated with the boiler 1101 and thus the boiler pressure may bemonitored by the controller 1105, used by the controller in processcontrol and also displayed on the display 1121. The pressure measuredmay also be used by the processor 1105 to control the operation of theair pump 1107 in response to the changing pressure conditions.

When the solenoid valve 1119 is open, pressurised air is introduced intothe steam boiler 1101. Accordingly, the air content of the steam boiler1101 can be increased with the introduction of pressurised air 1110 fromthe air pump or pressurised air source 1107. The operation of the airpump 1107, pressure controller 1108, flow control module 1109 andsolenoid valve 1119 are controlled by the controller 1105 in accordancewith user adjustable settings and by sensor devices such as thethermistor 1104 and the humidity sensor 1106. The output 1124 of thesteam boiler 1101 is regulated by, for example, a 3/2 solenoid outputcontrol valve 1111. The boiler's output control valve tilt is eitherfully closed, open to an atmospheric overflow 1112 or directed todischarge via a discharge line 1113 into the device's steam wand 1114.The pressure of the boiler discharge line 1113 is measured by a pressuresensor 1122 and communicated to the controller 1105. The pressure sensor1122 provides a signal which can be monitored by the controller, used bythe controller in process control and also to display information on thedisplay panel 1121 such as blockages in the wand 1114.

In some embodiments, the atmospheric discharge from the steam boiler isinto the device's drip tray 1117. The steam wand 1114 is associated witha temperature sensor 1115 (such as an NTC thermistor) and/or an optionalposition sensor 1116.

In one example, user inputs from the user operated controls 1118 provideinformation to the controller 1105 about the desired or targettemperature and froth texture of the finished froth product. From thisinput or inputs 1118, the controller 1105 determines the optimal airflow provided to the boiler 1101 and target temperature of the finishedproduct The controller 1105 then causes an opening of the output controlvalve 1111, causing the contents of the boiler 1101 to be dischargedinto and through the wand 1114. The controller 1105 closes the outputcontrol valve 1111 when the correct temperature signal, as measured andtransmitted by the wand's temperature sensor 1115 indicates that thecorrect final temperature has been reached. The position sensor 1116output allows the controller 1105 to cause the delivery of a purgingdose of steam through the wand 1114 when the wand has been returned to aresting position, as is known in the art.

Another embodiment is depicted in FIG. 13. In this example, thecontroller 1200 receives a manual user input from a variablepotentiometer 1201 or the like that relates to a user preferenceregarding final froth texture. The potentiometer 1201 directly regulatesthe operation of an air pump 1202. The signal from the potentiometer1201 to the controller 1200 is used by the controller 1200 to provideoptional feedback to the user regarding the selected setting of thepotentiometer 1201 on a display 1203 that is driven by the controller1200. In this example, the controller 1200 also receives inputs from atemperature sensor 1204 such as an NTC thermistor associated with orlocated in or on the steam wand 1205. The controller 1200 also receivesa signal input from a steam wand position sensor 1206. As with theprevious example, the position sensor 1206 and temperature sensor 1204allow the controller 1200 to deliver a purging dose of steam through thewand when the wand has been returned to a resting position, as is knownin the art.

In this example, the potentiometer 1201 regulates the output of a DC-DCconverter 1207 that is provided with a DC supply voltage 1208 from thecontroller 1200. The same voltage supply 1208 that is used to supply theconverter 1207, potentiometer 1201 and air pump 1202 also suppliesvoltage to a control valve such as a 3/2 type boiler output solenoid1209. Thus, the boiler output solenoid 1209 and air pump 1202 areswitched on and off simultaneously from the same output pin 1210 of thecontroller 1200, even though the amount (flow rate and pressure) of airdelivered by the pump 1202 is controlled by the manual or user operatedcontrol via the potentiometer 1201. When the boiler's output solenoidvalve 1209 is open, the contents of the steam boiler 1220 are dischargedby the valve 1209 into a venturi 1211.

The low pressure injector port 1212 of the venturi draws air dischargedby the pump 1202 through a one-way or check valve 1213 that preventsbackflow into the pump 1202. The steam and air are combined in theventuri 1211 and delivered through a common pipe or tube 1214 to thewand 1205. Thus, the ratio of steam to air is governed by both theperformance of the venturi 1211 and the output of the air pump 1202 asdetermined by the potentiometer 1201. Because of the shared pinarrangement 1210, the controller 1200 causes the simultaneous shut-offof the boiler's discharge valve 1209 and air pump 1202 when the correcttemperature has been reached, as determined by the wand's temperaturesensor 1204 working in conjunction with the controller 1200.

As shown in FIG. 14, an espresso making machine 1300 has within it asteam boiler 1301. In this example, the steam boiler has an integratedheating element 1302. Water is introduced into the steam boiler 1301 andis heated by the heating element to produce steam. The temperature ofthe contents of the steam boiler is monitored h a temperature sensor1303 such as an NTC thermistor that communicates with the device'selectronic controller 1304. In this, example, the steam boiler is alsoassociated with a humidity sensor 1305 that measures and communicatesthe humidity of the contents of the boiler to the controller 1304. Apressure sensor 1306 may also be associated with the boiler to monitorthe internal pressure and communication with the controller, so thecontroller may display boiler pressure or status and control the heatingelement 1302 operation in response to the changing pressure and/ortemperature conditions measured. A level sensor 1307 communicates withthe controller 1304 and allows the water level in the boiler to becontrolled to a level below that of the boiler's output 1308.

In this example, a pressurised air source 1309 which may be a positivedisplacement type pump under the control of the controller 1304 deliversan air supply directly to the boiler 1301.

Prior to or during the flow of steam out of the boiler, the air contentof the steam boiler can be increased with the introduction of air fromthe air pump 1309. The operation of the air pump 1309 is controlled bthe controller 1304 throughout an auto steam cycle in accordance withuser adjustable settings and by sensor devices such as the thermistor1303, humidity sensor 1305 or pressure sensors 1306, 1310.

The controller 1304 may provide, for example, a variable DC voltage 1311to control the motor, or PWM, AC frequency control, or otherwise asrequired. The air source 1309 can be continuously adjusted by thecontroller 1304 to provide differing quantities of air to the systemfrom full flow rate to no flow at all.

The output of the steam boiler is activated by, for example, a 3/2solenoid output control valve 1312. In the alternative, the output valve1312 may be manually activated. In some embodiments a manual outputvalve 1312 is a ceramic disk type valve with a position sensor thattransmits a position signal to the controller 1304 so that thecontroller may provide a graphic indication of the valve's manually setposition on the display 1322. The boiler's output control valve 1312 iseither fully closed, open to an atmospheric overflow 1313 or directed todischarge via a steam conduit 1314 into the device s steam wand 1315. Insome embodiments, the atmospheric discharge from the steam boiler isinto the device's drip tray 1316.

The controller activated opening of the output valve 1312, causes thesteam and air content of the boiler to be discharged through an optionalgas mixer 1326 and then through the wand 1315. The mixer 1326 locatedalong the steam discharge path better combines the air and steamdischarged from the boiler 1301. The controller 1304 closes the outputvalve 1312 when the correct temperature signal is received. Thetemperature is measured by the temperature sensor 1321 associated withthe milk jug 1318. In one example as shown in FIG. 14 the measuredtemperature is transmitted to the controller via a wirelesscommunication channel that uses a wireless communication method such asWIFI, Bluetooth or RFID which allows for communication of data to thecontroller 1304.

In one example, user inputs from the user operated controls 1317 provideinformation to the controller 1304 about die desired or targettemperature and/or froth texture of the finished froth product. Fromthis input or inputs, the controller 1304 determines the optimal airflow provided to the boiler and manages the control temperature controlmechanism that will result in the target temperature of the finishedproduct.

In some embodiments, the user interface 1317 is associated with a remoteaccessory such as a milk frothing jug 1318 having a processor 1324 thatis connected via a wireless interlace 1325 such as RFID to thecontroller 1304 via a wireless receiver 1325 a. In some embodiments thedata communication may be via a wired interface.

The communication of data and optionally power between the espressomaking machine 1300 and the remote accessory 1318 is controlled by thecontroller 1304. A power storage device 1319 such as an internalcapacitor or battery may be selectively charged when within range. Theremote accessory may have its own user interface controls or inputs 1320to define operation parameters relating to the finished froth productand sensing devices such as a temperature sensor 1321. The useradjustable input parameters may include froth amount or volume, desiredtemperature, starting and stopping steam flow or the like. The remotedevice may also allow for parameters to be displayed on the machine'sdisplay 1322 and/or the remote accessory device's own display 1323.

Details of a jug that includes a user control interface, a temperaturesensor and a data communication interface are provided elsewhere hereinwith reference to FIG. 30 through FIG. 32.

The steam wand 1315 may be associated with a position sensor 1327 whichallows for a cleaning cycle when returned to the initial upright or theborne position. The position sensor can also be used in conjunction withother parameters such as operation time, frequency of use or milktemperature to actively determine if a cleaning cycle is required. Whenrequired the controller 1304 provides a signal to the solenoid or outputvalve 1312 to deliver a purging dose of steam through the wand 1315 whenthe wand has been returned to a resting position. A dose of hot watermay also be used in another embodiment for the purpose of cleaning.

In one example a pressure sensor 1310 may also be placed incommunication with the steam conduit 1314 after the solenoid valve 1312.This sensor 1310 will enable the processor to display or indicate to theuser an indication for when the steam wand requires cleaning or toprovide an additional command, signal or voltage to the air pump for thedelivery of additional air to unblock an obstruction in the steam/airdelivery path, or to counteract changing, back pressure on air/steamratio performance.

By way of example only, an apparatus for making espresso coffee caninclude:

-   -   a body 1300 having a steam vessel 1301 and a pressurised air        source 1309 and a steam wand 1315; the steam vessel 1301 having        a heating element 1302 for providing a steam source; the        pressurised air source 1309 coupled to steam vessel for        delivering an air supply to the steam vessel 1301; the steam        wand 1315 being coupled to the steam vessel via an air-steam        flow path there between for receiving an air-steam source; an        output control valve 1312, located in the steam flow path,        controls the steam source there through;    -   an electronic controller module 1304 within the body; the        electronic controller module 1304 adapted to control operation        of the heating element, pressurised air source and, output        control valve;    -   a removable jug device 1318 including a processor element 1324        wirelessly couplable to the controller module 1304; the jug        device 1318 including a temperature sensor element 1321 for        measuring temperature of fluid within the jug; temperature        sensor element 1321 being coupled to processor element for        enabling the processor element to transmit a signal indicative        of a measured temperature to the control module; the steam wand        delivers an air-steam mixture to the fluid;

a user interface module 1317 coupled to the controller module forproviding user input to the controller module; the control modulereceives user input of a selected temperature and selected texture; thecontrol module, using the selected texture, determines a mixture of airand steam to specify an air-steam flow; the control module controls thepressurised air source and output control valve to deliver the specifiedair-steam flow during a frothing cycle; the control module receives thesignal indicative of the measured temperature and closes the dischargevalve when the measured temperature reaches the selected temperature toend the frothing cycle.

By way of example only, an apparatus for making espresso coffee caninclude;

-   -   a body 1300 having a steam vessel 1301 and a pressurised air        source 1309 and a steam wand 1315; the steam vessel 1301 having        a heating element 1302 for providing a steam source; the        pressurised air source 1309 coupled to steam vessel for        delivering an air supply to the steam vessel 1301; the steam        wand 1315 being coupled to the steam vessel via an air-steam        flow path there between for receiving an air-steam source; an        output control valve 1312, located in the steam flow path,        controls the steam source there through;    -   an electronic controller module 1304 within the body; the        electronic controller module 1304 adapted to control operation        of the heating element, pressurised air source and output        control valve;

a removable jug device 1318 including a processor element 1324wirelessly couplable to the controller module 1304; the jug device 1318including a temperature sensor element 1321 for measuring temperature offluid within the jug; temperature sensor element 1321 being coupled toprocessor element for enabling the processor element to transmit asignal indicative of a measured temperature to the control module; thesteam wand delivers an air-steam mixture to the fluid;

a user interface module 1317 coupled to the controller module forproviding user input to the controller module; the control modulereceives user input of a selected temperature and selected texture; theuser interface including a variable user input for specifying theselected texture; the variable user input directly regulates theoperation of an air pump 1202 that provides the pressurised air source;the variable user input provides a feedback signal to the controller forindicating the selected texture; the control module activates thepressurised air source and output control valve to deliver the specifiedair-steam flow during a frothing cycle; the control module receives thesignal indicative of the measured temperature and closes the dischargevalve when the measured temperature reaches the selected temperature toend the frothing cycle.

Milk Frothing Apparatus with Controlled Airflow

In existing automatic milk froth systems it is difficult to achieve ahigh quality frothed milk consistency and reliability. Cleaning is anissue with existing temperature sensor construction within the tip ofthe steam wand.

In an example embodiment air flow from a precisely controlled source ofpressurized air can be combined with the steam path allowing adjustablefrothing and texturing of milk. A steam and air mixture is outputthrough the steam wand that is submergible in a milk jug. A heating andfrothing cycle may be dependent on temperature feedback of the milk asmeasured by a temperature sensor (for example in the base of the jug orin the base of the frothing apparatus itself). A user can select orprogram profiles for different types of milk. (i.e. full fat, skim, soy,etc.). The resulting steam/air mix is then combined with milk in a jugthrough the submergible steam wand. Addition of air cycle stages aredependent on the feedback from, for example, a milk jug sensor.

In some embodiments, a cleaning purge cycle is selectively and/orautomatically initiated. A cleaning steam pulse can be applied when thesteam wand is returned to a home position (e.g. automatically using aspring loaded and dampened mechanism). Cleaning can be automated usingthe biased steam wand and a cleaning steam pulse. Sensor feedback of thewand position and/or previous cycle data may also be used as input datato the cleaning process (i.e. cleaning may not be required if the milkis not heated).

In an embodiment, the frothing apparatus has a source of steam, a sourceof pressurized air, one or more air pressure sensors associated withports on a mixing component (i.e. a venturi, an ejector or a T-junctioncomponent), and a control module coupled to the air pressure sensor forcontrolling the air source such that air pressure applied to the mixingdevice is sufficient to provide a pressure differential. The controlledpressure differential allows for a variable airflow into the steam path.

A temperature sensor for measuring temperature of the milk in a jug(e.g. associated with base of the frothing jug) can be coupled to thecontrol module to enable adjustments to the steam source and air sourceas described elsewhere herein.

In some embodiments the control module receives sensor signals thatmeasure operating conditions, and calculates parameters for controllingthe air source and/or the steam source accordingly. Controlledcomponents such as the steam source and air pressure can be continuouslyadjusted throughout the steam cycle using a control logic loop.

It will be appreciated that an embodiment can, by way of example only,provide one or more of the following advantages:

-   -   providing a more precise control air injection into steam path        allowing for improved milk froth quality    -   providing automatic adjustment of air pump parameters to        compensate for changes to operating conditions (i.e. steam flow,        boiler pressure, air pump pulses, and wand back pressure)    -   providing an ability to use different control profiles based on        milk type, (i.e. soy, skim milk, full fat, etc.) This can be        achieved by tuning operating parameters which can affect the end        result of milk type products.    -   enabling lower cost of configuration by using a small pump when        compared to existing competing systems.

FIG. 15 and FIG. 16 show example plumbing and control schematics forexample embodiments.

Referring to FIG. 15, an example espresso making machine 1500 includes aboiler 1520, pressure transducer and milk temperature sensor (NTC)associated with base of the espresso making machine 1500.

This example embodiment apparatus 1500 includes a water source 1510 forproviding water, typically through a filter cartridge 1312 which isconveyed by a pump 1514 to a boiler 1520. The flow line 1515 leading tothe boiler has an overpressure value 1516 that leads to an overflow path1517 to the drip tray 1518. The boiler also has a vacuum breather valve1519 that is in fluid flow communication with the drip tray.

A processor module 1530 monitors operation of the boiler 1520 through alevel sensor 1521 and/or a pressure sensor 1522 (for example aPiezoresistive strain gauge pressure transducer) and/or a thermal fuse1523 and/or a thermostat 1524. The water tank 1510 can further include awater level sensor 1513, coupled to the processor module 1530, formonitoring water availability.

A solenoid 1540 controls release of steam flow to a steam wand 1542 viaan air injector module 1544 and an optional static mixer 1549. The airinjector module includes a primary steam flow path 1545, an airinjection path 1546 and an outflow 1547. By way of example, the airinjection module can incorporate a venturi. The air injection flow path1546 can receive pressured air delivered by an air pump 1550 typicallythrough a one way valve 1552. A pressure sensor 1554 is coupled to theair ingress flow path 1546. The pressure sensor 1554 provides pressuremeasurements to the processor module 1530.

It will be appreciated that with the air pump 1550 turned off(disabled), the pressure sensor can monitor a base level pressureprovided by the injection module caused by the steam air flow and anyback pressure provided by the steam wand. With the air pump 1550activated to varying power levels (0%-100%) the pressure sensor monitorsthe pressure in the air ingress flow path, allowing for control of thepump.

It would be further appreciated that, with the air pump activated (powercould be from 0%-100%), if the measured pressure is greater than thebackground pressure measured with the air pump off, then air will beinjected into the steam flow path, then mixed and delivered to the steamwand.

A temperature sensor 1556 monitors the temperature of the milk, andprovides a temperature signal to the process module 1530.

The processor module 1530 is coupled to a user interface 1560 comprisinga display element 1562 and a plurality of user input elements 1564.

In an embodiment, a descale valve 1570 can enable direct flow from theboiler to the drip tray.

In some embodiments the frothing apparatus as described herein is notnecessarily associated with or integral with an espresso making machine.

Referring to FIG. 16, an example frothing apparatus 1600 includes aheating element transducer system, pressure transducer and milktemperature sensor (NTC) associated with a jug. FIG. 16 shows anembodiment using a flow through steam element in place of the steamboiler of the embodiment 1500. The temperature sensor can be removablefrom the jug as described in more detail elsewhere herein.

The frothing apparatus 1600 includes a water source 1610 for providingwater, optionally through a filter cartridge 1612, which is conveyed bya pump 1614 to a steam element 1620. The flow line 1615 leading to thesteam element has an overpressure value 1616 that leads to an overflowpath 1617 to the drip tray 1618.

A processor module 1630 monitors operation of the steam element 1620through a pressure sensor (e.g. a Piezoresistive strain gauge pressuretransducer), and/or a temperature sensor 1622 (for example an NTCthermistor) and/or a thermal fuse 1623 and/or a thermostat 1624. Thewater tank 1610 can further include a water level sensor 1613, coupledto the processor module 1630, for monitoring water availability.

A solenoid 1640 controls release of steam flow to a steam wand 1642 viaan air injector module 1644 and an optional static mixer 1649. Thestatic mixer can allow for further combining of the steam fluid, makingit more homogenous. The air injector module includes a primary steamflow path 1645, an air injection path 1666 and an outflow 1647. By wayof example, the air injection module can incorporate a venturi. The airinjection flow path 1646 can receive pressured air delivered by an airpump 1650 typically through a one way valve 1652. A pressure sensor 1654is coupled to the air ingress flow path 1646. The pressure sensor 1654provides pressure measurements to the processor module 1630.

It will be appreciated that with the air pump turned off (disabled), thepressure sensor can monitor a base level pressure provided by theinjection module caused by the steam air flow and any back pressureprovided by the steam wand. With the air pump actuated (enabled), thepressure sensor monitors the pressure in the air ingress flow path.

It would be further appreciated that, with the air pump enabled, if themeasured pressure is greater than the background pressure measured withthe air pump off, then air will be injected'into the steam flow path,then mixed and delivered to the steam wand.

In this example embodiment, a temperature sensor 1656, associated withthe jug, monitors the temperature of the milk and provides a temperaturesignal to the process module 1630.

The processor module 1630 is coupled to a user interface 1660 comprisinga display element 1662 and a plurality of user input elements 1664.

FIG. 17 shows an embodiment flow chart 1700 for a method performed by aprocessor module for providing and monitoring production of frothingmilk.

By way of example only, the method 1700 includes any one or more of thefollowing steps:

-   -   STEP 1702: receiving user input or activating auto froth cycle        proceed to STEP 1704;    -   STEP 1704: activate the steam flow to the wand, present status        to the user display, and proceed to STEP 1706;    -   STEP 1706: compare measured milk temperature with a first        predetermined or threshold temperature (e.g. 60 degrees        Celsius), it measured milk temperature is less than the        threshold temperature then proceed to STEP 1708, otherwise        proceed to STEP 1734;    -   STEP 1708: if a no-air timer has exceeded a first predetermined        time (e.g. 2 seconds) proceed to STEP 1710, otherwise proceed to        STEP 1706;    -   STEP 1710: disable the air pump, measure the air pressure, then        calculate a pressure set point (for example the pressure set        point may be calculated by combining the base-line air        pressure+a user adjustable offset variable based on milk type+a        rate of change of pressure calculation); proceed to STEP 1711;    -   STEP 1711: enable air pump (for example at or above 50%);        proceed to STEP 1712;    -   STEP 1712: if measured milk temperature is less than a first        predetermined or threshold temperature (e.g. 50 degrees Celsius)        proceed to STEP 1714 otherwise proceed to STEP 1722;    -   STEP 1714: if the air pump timer has not exceeded a second        predetermined time (e.g. 1 seconds) proceed to STEP 1710        (enabling for re-measurement of baseline pressure, and        subsequent calculation of next pressure set point), otherwise        proceed to STEP 1722;    -   STEP 1716: if measured air pressure is less than a minimum        threshold (e.g. 5 psi) disable the air pump (at 1717) and        proceed to STEP 1712, otherwise proceed to STEP 1718;    -   STEP 1718 if the measured air pressure is less than the set        point increase the air pump power (at 1719) and proceed to STEP        1712, otherwise proceed to STEP 1720;    -   STEP 1720: if the measured air pressure is greater than the set        point decrease the air pump power (at 1721) and proceed to STEP        1712, otherwise proceed to STEP 1712;    -   STEP 1722: disable the air pump, proceed to STEP 1724;    -   STEP 1724: if the milk temperature is greater than a target        temperature (e.g. 60 degrees Celsius) proceed to STEP 1726,        otherwise wait at STEP 1724;    -   STEP 1726: deactivate the steam flow, present die status to the        user display, and proceed to STEP 1728;    -   STEP 1728: if the air pressure profile required was greater than        a pre-determined maximum (blockage) threshold pressure proceed        to STEP 1730 (enabling detection of operation parameters for        concluding if there is a restriction in steam tip, which        degrades the performance and consistency of system), otherwise        proceed to STEP 1732;    -   STEP 1730: present status to user indicating the steam wand may        be blocked and proceed to STEP 1732;    -   STEP 1732: proceed to complete the auto froth cycle;    -   STEP: 1734: disable steam flow, present status to user, and        proceed to STEP 1736;    -   STEP 1736: proceed to complete the auto froth cycle.

It will be appreciated that in this embodiment flow chart 1700, eachtemperature and timer value is provided by way of example only and maybe adjustable and/or calculated by a processor module and/or havedifferent pre-determined values. As the process provides ongoingmonitoring of the temperature and pressure provided by the steam wand,the user can adjust a set temperature and/or froth settings and/or milktype at any time during the cycle. The user can also stop a cycle at anypoint.

It would also be appreciated that during a froth cycle, the air pressurecontrol loop may cause the air pressure set point to increase over timeusing a rate change calculation that provides an estimate prediction forthe air pressure set point during the pump time cycle based on previousair pressure readings.

FIG. 18 is an example graph 1800 that shows pressure measurements duringa portion of a froth cycle.

The graph 1800 shows a line 1810 that depicts measured air pressure, anda line 1820 that depicts a pressure controlled set point over time. Thisis overlaid with line 1830 that depicts the pump power over time.

It will be appreciated that the line 1820, in this example, ispiece-wise linear or stepped-continuous for providing a controlledpressure set point.

In this example, the air pump is disabled periodically (for exampleevery 0.6 seconds at 1812), to enable the pressure transducer to measurea base pressure. After measuring a base pressure, an offset is appliedto provide a control pressure set point for the sample time period (at1822), allowing the control loop to control the air pump to providepressure measured at the pressure transducer that is about the controlpressure set point.

It would be observed from the graph 1800, that the base pressure changesover time, for example due to back pressure provided by the milk duringthe process, the boiler pressure, and any blockages in the steam wand.By periodically monitoring the background pressure, and reapplyingand/or calculating an appropriate offset pressure, the air pump can becontrolled to counteract any fluctuations in background pressure andthereby provide a more reliable mix ratio between the steam flow and airflow. It would be appreciated that the graph 1800 depicts a stepwiseapproximation for the control pressure set point, which can be changedto a linear prediction.

In an alternative embodiment, by way of example only, the pressurecontrol set value can also vary over time during (or within) a sampleperiod by modelling or predicting a base pressure during that sampleperiod (based on past samples). It will be appreciated that aninterpolation (e.g. at 1824) can be made based on past samples (e.g. at1826). Any appropriate model/interpolation technique can be employed.

By monitoring the changes in pressure, the injected air flow can betuned for a particular milk type and froth setting, and can also enablethe detection of blockages in the steam wand or flow path. Operation ofthe steam wand can be substantially automated or semi-automated.

FIG. 19A and FIG. 19B show an embodiment milk frother apparatus 1900, byway of example only, having a semi-automated steam wand 1910. The steamwand 1910 has a steam nozzle 1912 and a steam tip 1914.

In this embodiment, the steam wand can be raised and loweredsemi-automatically. The steam wand can be raised and lowered by rotationabout an axis 1920 by a drive gear 1922 acting on a driven gear 1924.The steam wand can be biased to a lowered configuration (as shown inFIG. 19A) by a torsion spring 1926. A switch 1928 is operativelyassociated with the wand assembly, such that it can provide a signal toa processor module 1930 indicative of the wand being in either theraised or lowered configuration.

Moving the steam wand to a raised configuration (as shown in FIG. 19B)enables the assembly to engage a releasable lock mechanism for retainingthe wand in the raised configuration. In this example embodiment, thewand assembly has a detent 1940 that, when the assembly is rotated tothe raised configuration, engages a biased locking pin 1942. The lockingpin is defined, by way of example only, as a “pogo” pin that is biasedby a compression spring.

Referring to FIG. 20A through FIG. 20F milk can be frothed by theapparatus 1900 (at 2010). The jug can then be removed (at 2020), causingit to engage the steam wand (at 2030), moving the steam wand to theraised configuration (at 2040), the wand (once in the raisedconfiguration) can be semi-automatically lowered to a loweredconfiguration (at 2050), enabling a wand dean operation to commence (at2060).

Referring to FIG. 21A and FIG. 21B, this process can be furtherautomated by monitoring the state of the steam wand in the raisedconfiguration. By way of example only, the locking mechanism, canprovide a signal to the processor module for confirming the wand iscurrently in the raised configuration.

FIG. 21A and FIG. 21B show an embodiment milk frother apparatus 2100, byway of example only, having an automated steam wand 2110. The steam wand2110 has a steam nozzle 2112 and a steam tip 2114.

In this embodiment, the steam wand can be raised and loweredautomatically. The steam wand can be raised and lowered by rotationabout an axis 2120 by a motorised drive gear 2222 acting on a drivengear 2224. The steam wand can be biased to a lowered configuration (asshown in FIG. 21A) by a torsion spring 2126. A switch 2128 isoperatively associated with the wand assembly, such that it can providea signal to a processor module 2130 indicative of the wand being ineither the raised or lowered configuration.

Moving the steam wand to a raised configuration (as shown in FIG. 21B)enables a sensor 1242 to detect the assembly being in the raisedconfiguration. In this example embodiment, the sensor is coupled to theprocessor module for providing a signal indicative of the wand assemblybeing in the raised configuration.

Referring to FIG. 22A through FIG. 22F, milk can be frothed by theapparatus 2100 (at 2210). The jug can then be removed (at 2220), causingthe steam wand to raise (at 2230), the steam wand is moved to the raisedconfiguration (at 2240), the wand (once in the raised configuration) canbe automatically lowered to a lowered configuration (at 2250), enablinga wand clean operation to commence (at 2260).

FIG. 23 shows an example embodiment drip tray 2300 having an, inbuilttemperature sensor.

In this example embodiment, the drip tray provides a support surface2310 for receiving a jug during a milk froth operation. A temperaturesensing assembly 2320 is biased to an exposed configuration, such that atemperature sensing surface 2321 protrudes though (and is above) thesupport surface 2310 for enabling the sensor to engage and thermallycouple with a supported jug. Placing a jug on the temperature sensorcauses it to lower against a bias such that thermal coupling ismaintained.

In this embodiment, the temperature sensor assembly 2320 includes anegative temperature coefficient (NTC) sensor 2322 that is electricallycoupled to a socket portion 2323. The drip tray defines a reservoirportion 2312 about the temperature sensing assembly 2320. Thetemperature sensing assembly 2320 has a chassis 2324 that slidablyengages through a floor potion 2314 of the reservoir, and is biased intoa raised configuration by a compression spring 2325. An O-ring seal 2326and flexible cover 2327 are provided to seal the temperature sensingassembly 2320 from the reservoir 2312. The temperature sensing assembly2320 can include an abutment surface 2328 that engages the drip traysupport surface 2310 for limiting the height of the temperature sensingsurface 2321 when in the raised configuration. The support surface 2310is typically provided in the form of a perforated platform that isremovable for cleaning. It will be appreciated that the drip trayprovides a reservoir 2312 about the temperature sensing assembly 2320.

FIG. 24 shows the drip tray 2300, having the temperature sensingassembly 2320 in a raised configuration. FIG. 25 shows the drip tray2300, having the temperature sensing assembly 2320 in a loweredconfiguration (biased upwards).

FIG. 26A and FIG. 26B show the drip tray 2300 can be removably coupledto a coffee making and/or milk frothing apparatus 2600. It will beappreciated that the drip tray apparatus 2300 is typically removed forcleaning. Electrical contacts 2610 engage the coupling 2323 when thedevice is engaged with the apparatus 2600, for enabling a processormodule to monitor temperature.

FIG. 27A and FIG. 27B show an embodiment coffee making and/or milkfrothing apparatus 2700 releasably engagable with a drip tray 2750 thatenables waste water/steam ingress to the drip tray.

It will be appreciated that, when a drip tray is coupled to an apparatusthat requires waste water to egress from the apparatus to the drip tray,the drip tray can be further configured with a separate, ingress porttypically associated with or located about the coupling.

FIG. 27A shows a coffee making apparatus or milk frothing apparatus 2700laving a steam/waste water egress 2710 that engages the drip tray 2750in fluid communication with an ingress port 2752. This fluid flowcoupling can be made with or without electrical coupling for atemperature sensor.

Referring to FIG. 27B, a one way valve 2754 can be provided to restrictwater held in the drip tray from spilling as the drip tray is removedfrom the apparatus. The one way valve can be automatically opened as thedrip tray is coupled to the apparatus, and automatically closed as thedrip tray is removed or separated from the apparatus. Fluid sealing ofthe coupling can be provided (for example using an O-ring or othersealing means).

FIG. 28 shows an example embodiment drip tray 2800 that includes acoupling clement 2810. This coupling element, by way of example only,includes an ingress flow path 2812 for receiving waste water/steam andan electrical coupling 2814 for communicating a temperature signal froma temperature sensor 2816. FIG. 29 shows an enlarged view of thecoupling element 2810.

FIG. 30A through FIG. 32B show an embodiment jug 3000 for frothing milk.It will be appreciated that this jug can be used with apparatusdisclosed herein.

In this example embodiment, the jug 3000 includes a body (or vessel)3010 having a removable attachable handle 3020. It will be appreciatedthat the handle 3020 can be removed to allow the body 3010 to beseparately cleaned or washed.

The body 3010 and handle 3020 have respective coupling elements (forexample, 3030A-3030B and 3032A-3032B) for releasably coupling the handle3020 to the jug 3000. In an example embodiment a release mechanism suchas a button 3034 is associated with a coupling element (for example,coupling element 3032B) for releasing coupling to a respective couplingelement on the jug (for example coupling element 3032A).

The handle 3020 further includes a controller element 3040 forcommunicating data (or data signals) to a cooperating frothing apparatus(not shown). The data communication can be via wired or wirelesscommunication. In this embodiment, the controller element is coupled toa temperature sensor 3042 for monitoring the temperature of liquid inthe vessel. As shown here, the temperature sensor is supported by thehandle, and comes into thermal coupling with the jug when the handle isattached. The temperature sensor 3042 is biased toward the jug 3000 forenhancing thermal coupling with the jug when the handle 3020 isattached. For example, the temperature sensor 3042 is biased by a spring3044 (or other biasing is means) into the thermal coupling with the jug,as best shown in FIG. 31B.

The handle 3020 can further include one or more user interface inputelements (for example, function selection buttons or switches) 3046 thatare coupled to the controller element 3040. As shown, the user interfaceincludes two toggle buttons, for toggling through temperature and frothsettings. It will be appreciated that any number of user interfacecontrols may be used for this type of application, for example a slidingcontrol.

User selection of the input elements can be monitored and/or used by thecontroller element 3040 for controlling features of the jug 3000. Userselection of the input elements may be transmitted to a controllermodule in the frothing apparatus for providing user input to theapparatus.

It would be appreciated that an embodiment handle may also include adisplay element (not shown).

In some embodiments communication between the controller element 3040and associated frothing apparatus is one-directional, and datapertaining to the user settings entered via the input elements 3046 iscommunicated to the frothing apparatus and used to control the frothingprocess.

In other embodiments communication is bi-directional for the purpose ofcommunication management (e.g. sending data receipt acknowledgementsand/or resending data in the event of a transmission error), and/or forthe purpose of providing data from the frothing apparatus controllerback to the jug (e.g. operation status information that is displayed ona handle display or conveyed via the user interface in the form ofcoloured LED lights).

As shown in FIG. 32B, an embodiment handle 3020 includes a plurality ofcoupling elements (for example, 3030B and 3032B) that couple torespective coupling elements on the jug 3000 (for example 3030A and3032A).

It would be appreciated that a controller element 3040 can also beassociated with one or more additional/alternative sensors (not shown)for monitoring operation of the jug.

As described with reference to 14, the power required by the electronicson the handle 3020 can be provided by a wired or wireless connectionfrom the cooperation apparatus or machine (i.e. a standalone frotherapparatus or an espresso making machine). For the embodiment shown here,the handle 3020 includes a power storage (not shown) that is charged viaa wireless connection with a milk frother adapted to receive the jug3000 and adapted to charge the jug handle power storage. In someembodiments data regarding depleted power is indicated on the handleuser interface and/or communicated to the cooperating apparatus ormachine and, where appropriate, used as an input to a rechargingprocess.

It with be appreciated, by way of example only, that a jug may be usedwith a frothing apparatus. The jug comprising:

-   -   a vessel body for holding a liquid to be heated;    -   a handle attached to the vessel body, the handle for holding the        jug;    -   a user interface for receiving an operation-related user input;    -   a communication means adapted to communicate data associated        with the jug to the frothing apparatus; and    -   a controller for controlling the user interface and the        communication means.

It will be further appreciated, by way of example only, that a frothingapparatus can be adapted to cooperate with a jug for heating a liquid inthe jug. The frothing apparatus comprising;

-   -   a steam heater, a steam nozzle, and a steam path providing fluid        communication from the steam heater to the steam nozzle for        delivering heating steam to the jug;    -   communication means adapted to receive operating data from a        cooperating communication means associated with the jug, the        data comprising an operation-related user input; and    -   a controller for controlling operation of the steam heater and        the steam path based on the operation-related user input.

It will be further appreciated, by way of example only, that an espressomaking machine can comprising a frothing apparatus as taught by any onethe embodiments suggested herein. The frothing apparatus can be furtheradapted to cooperate with (or include) a jug as taught by any one theembodiments suggested herein.

Interpretation

It will be appreciated that the illustrated embodiments provide anapparatus for milk frothing.

Although the invention has been described with reference to specificexamples, it will be appreciated by those skilled hi the art that theinvention may be embodied in many other forms.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure or characteristicdescribed in connection with the embodiment is included in at least oneembodiment of the present invention. Thus, appearances of the phrases“in one embodiment” or “in an embodiment” in various places throughoutthis specification are not necessarily all referring to the sameembodiment, but may. Furthermore, the particular features, structures orcharacteristics may be combined in any suitable manner, as would beapparent to one of ordinary skill in the art from this disclosure, inone or more embodiments.

In the claims below and the description herein, any one of the termscomprising, comprised of or which comprises is an open term that meansincluding at least the elements/features that follow, but not excludingothers. Thus, the term comprising, when used in the claims, should notbe interpreted as being limitative to the means or elements or stepslisted thereafter. For example, the scope of the expression a devicecomprising A and B should not be limited to devices consisting only ofelements A and B. Any one of the terms including or which includes orthat includes as used herein is also an open term that also meansincluding at least the elements/features that follow the term, but notexcluding others. Thus, including is synonymous with and meanscomprising.

Similarly, it is to be noticed that the term coupled, when used in theclaims, should not be interpreted as being limitative to directconnections only. The terms “coupled” and “connected”, along with theirderivatives, maybe used. It should be understood that these terms arenot intended as synonyms for each other. Thus, the scope of theexpression a device A coupled to a device B should not be limited todevices or systems Wherein an output of device A is directly connectedto an input of device B. It means that there exists a path between anoutput of A and an input of B which may be a path including otherdevices or means. “Coupled” may mean that two or more elements areeither in direct physical, or that two or more elements are not indirect contact with each other but yet still co-operate or interact witheach other.

As used herein, unless otherwise specified the use of the ordinaladjectives “first”, “second”, “third”, etc., to describe a commonobject, merely indicate that different instances of like objects arebeing referred to, and are not intended to imply that the objects sodescribed must be in a given sequence, either temporally, spatially, inranking, or in any other manner.

As used herein, unless otherwise specified the use of terms“horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well asadjectival and adverbial derivatives thereof (e.g., “horizontally”,“rightwardly”, “upwardly”, etc.), simply refer to the orientation of theillustrated structure as the particular drawing figure faces the reader,or with reference to the orientation of the structure during nominaluse, as appropriate. Similarly, the terms “inwardly” and “outwardly”generally refer to the orientation of a surface relative to its axis ofelongation, or axis of rotation, as appropriate.

Similarly it should be appreciated that in the above description ofexemplary embodiments of the invention, various features of theinvention are sometimes grouped together in a single embodiment, figure,or description thereof for the purpose of streamlining the disclosureand aiding in the understanding of one or more of the various inventiveaspects. This method of disclosure, however, is not to be interpreted asreflecting an intention that the claimed invention requires morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive aspects lie in less than allfeatures of a single foregoing disclosed embodiment. Thus, the claimsfollowing the Detailed Description are hereby expressly incorporatedinto this Detailed Description, with each claim standing on its own as aseparate embodiment of this invention.

Furthermore, while some embodiments described herein include some hutnot other features included in other embodiments, combinations offeatures of different embodiments are meant to be within the scope ofthe invention, and form different embodiments, as would be understood bythose in the art. For example, in the following claims, any of theclaimed embodiments can be used in any combination.

Furthermore, some of the embodiments arc described herein as a method orcombination of elements of a method that can be implemented by aprocessor of a computer system or by other means of carrying out thefunction. Thus, a processor with the necessary instructions for carryingout such a method or element of a method forms a means for carrying outthe method or element of a method. Furthermore, an element describedherein of an apparatus embodiment is an example of a means for carryingout the function performed by the element for the o purpose of carryingout the invention.

In the description provided herein, numerous specific details are setforth. However, it is understood that embodiments of the invention maybe practiced without these specific details. In other instances,well-known methods, structures and techniques have not been shown indetail in order not to obscure an understanding of this description.

Thus, while there has been described what are believed to be thepreferred embodiments of the invention, those skilled in the art willrecognize that other and further modifications may be made theretowithout departing from the spirit of the invention, and it is intendedto claim all such changes and modifications as fall within the scope ofthe invention. For example, any formulas given above are merelyrepresentative of procedures that may be used. Functionality may beadded or deleted from the block diagrams and operations may beinterchanged among functional blocks. Steps may be added or deleted tomethods described within the scope of the present invention.

It will be appreciated that an embodiment of the invention can consistessentially of features disclosed herein. Alternatively, an embodimentof the invention can consist of features disclosed herein. The inventionillustratively disclosed herein suitably may be practiced in the absenceof any element which is not specifically disclosed herein.

1. A method of performing a frothing cycle for milk in a frothingapparatus container by injecting steam mixed with air into the milk inthe container, the method comprising the steps of: 1a) determining aback pressure of a wand having a distal end that is submersible in milkin the container; 1b) determining a pressure set point, dependent uponthe determined back pressure and a desired pressure profile, to beestablished by an air pump; and 1c) enabling the air pump at a pumppower dependent upon the determined pressure set point.
 2. A methodaccording to claim 1, further comprising, prior to the determining ofthe wand back pressure, the steps of: 2a) receiving a frothing cyclecommand; and 2b) activating a flow of steam to the wand.
 3. A methodaccording to claim 1, further comprising determining, prior to thedetermining of the wand back pressure, if a temperature of the milk inthe container is less than a predetermined temperature, and disablingthe air pump.
 4. A method according to clam 2, further comprising, afterthe step (2b) and prior to the step (1b), the steps of: 4a) if thetemperature of the milk in the container exceeds the predeterminedtemperature; 4aa) disabling the flow of steam; 4ab) presenting statusinformation; and 4ac) concluding the frothing cycle for the milk in thecontainer.
 5. A method according to claim 3, wherein the steps (1a),(1b), and (1c) are performed only if the air pump has been inactive formore than a first time-period.
 6. A method according to claim 1,comprising, after the step (1c), the steps of: if the temperature of themilk in the container is less than the predetermined temperature,periodically performing the steps (1a), (1b), and (1c).
 7. A methodaccording to claim 6, wherein if the temperature of the milk in thecontainer is less than the predetermined temperature, periodicallyperforming the steps of; 7a) if the wand back pressure is less than aminimum threshold, disabling the air pump; 7b) if the wand back pressureis not less than the minimum threshold and is less than the pressure setpoint, increasing the air pump power; and 7c) if the wand back pressureis not less than the minimum threshold and is greater than the pressureset point, decreasing the air pump power.
 8. A method according to claim6, wherein if the temperature of the milk in the container is greaterthan the predetermined temperature: 8a) disabling the air pump; 8b) ifthe temperature of the milk in the container is greater than a targettemperature; 8ba) disabling the flow of steam; and 8bb) presentingstatus information; 8c) if the wand back pressure is greater than ablockage threshold; 8ca) presenting blockage status information; and8cb) concluding the frothing cycle for the milk in the container.
 9. Anapparatus for performing a frothing cycle for milk in a frothingapparatus container by injecting steam mixed with air into the milk inthe container, the apparatus comprising: a processor; a steam source forproviding a flow of steam to a steam wand having a distal end that issubmersible in the milk in the container; the steam wand; a temperaturesensor for measuring a temperature of the milk in the container; an airpump for providing a flow of air to the steam wand; a pressure sensorfor measuring back pressure of air in the steam wand; and anon-transitory tangible storage device storing a software program fordirecting the processor to perform a method comprising the steps of: 9a)determining a back pressure of the wand; 9b) determining a pressure setpoint, dependent upon the determined back pressure and a desiredpressure profile, to be established by the air pump; and 9c) enablingthe air pump at a pump power dependent upon the determined pressure setpoint.
 10. An apparatus according to claim 9, wherein the method furthercomprises, prior to the determining of wand back pressure, the steps of:10a) receiving a frothing cycle command; and 10b) activating a flow ofsteam to the wand.
 11. An apparatus according to claim 9, wherein themethod further comprises determining, prior to the determining of thewand back pressure, if a temperature of the milk in the container isless than a predetermined temperature and disabling the air pump.
 12. Anapparatus according to claim 9, wherein the steam source is a boiler.13. An apparatus according to claim 9, wherein the steam source is aflow through steam element.
 14. A tangible, non-transitory computerreadable medium storing a computer program for directing a processor toperform a frothing cycle for milk in a frothing apparatus container byinjecting steam mixed with air into the milk in the container, themethod comprising the steps of: 14a) determining a back pressure of awand having a distal end that is submersible in the milk in thecontainer; 14b) determining a pressure set point, dependent upon thedetermined back pressure and a desired pressure profile, to beestablished by an air pump; and 14c) enabling the air pump at a pumppower dependent upon the determined pressure set point.
 15. A computerreadable medium according to claim 14, further comprising, prior to thedetermining of the wand back pressure, the steps of: 15a) receiving afrothing cycle command; and 15b) activating a flow of steam to the wand.16. A computer readable medium according to claim 15, wherein the methodfurther comprises determining, prior to the determining of the wand backpressure, if a temperature of the milk in the container is less than apredetermined temperature and disabling the air pump.